1. Field of the Invention
The present invention relates to an electrophoretic display device. More particularly, the present invention relates to a display substrate and a method of manufacturing the display substrate.
2. Description of the Related Art
An electrophoretic display device is a type of flat display device which may be used for an electronic book or other similar device. Generally, the electrophoretic display device includes a first substrate having a first electrode, a second substrate having a second electrode and a microcapsule having a white pigment particle and a black pigment particle. The microcapsule is interposed between the first and second substrates. Either the white or the black pigment particle is positively charged, and the other pigment particle is negatively charged.
A predetermined voltage is applied to the first and second electrodes to generate an electric field. As a result, the white and black pigment particles move toward the electrode having an opposite polarity in comparison to the respective moving pigment particle.
The electrophoretic display device has a high reflectivity and a high contrast ratio compared to a liquid crystal display device, and a viewing angle of the electrophoretic display device is not limited, similar to when viewing a sheet of paper, for example. Furthermore, the electrophoretic display device has a bistable characteristic. Thus, the electrophoretic display device may maintain display of an image, even when the electrophoretic display device does not continuously receive a voltage. Therefore, power consumption is reduced as compared to devices which do not have the bistable characteristic.
However, the electrophoretic display device does not have a black matrix which blocks an outside light and covers a remaining region which is not covered by the electrodes.
Furthermore, when the electrophoretic display device has a plurality of the microcapsules, an individual microcapsule is connected to an adjacent individual microcapsule by a binder. Light may leak through the binder, reducing a contrast ratio of the electrophoretic display device. A method of reducing a size of the microcapsule to reduce a space through which the light leaks has been suggested to solve the above-mentioned problem, but the suggested method may cause collisions between adjacent individual microcapsules of the plurality of microcapsules.